It is necessary to periodically test aviation fuel to determine whether the fuel has been contaminated by the presence of free water.
Among the techniques employed to achieve the desired testing includes the filling of a container with a quantity of the fuel to be tested. A fixture having an extending hypodermic needle is disposed at the bottom of the container. A glass vial having a rubber stopper is urged against the needle causing the needle to extend through the rubber stopper. The interior of the glass vial is under vacuum causing the fuel to be tested to be drawn into the vial. A powdered chemical, previously inserted into the vial, is contacted by the incoming fuel. In the event the fuel contains more than the acceptable amount of water, typically 30 ppm, the chemical changes color.
The act of drawing a sample of fuel from the fueling system into an open container is messy and also allows the introduction of additional contamination such as water from rain, for example. Such a procedure introduces an undesirable source of an error in the test.
It would be desirable to produce a system for collecting a sample of aviation fuel to test for the presence of free water wherein the fuel to be tested can be caused to flow directly from an aircraft fuel handling system into an optically transparent vial containing a powdered chemical which changes color upon contact with free water.